

Why 8 Gluons?
Name: Ricardo
Status: student
Age: 19
Location: N/A
Country: N/A
Date: 20002001
Question:
Why 8 gluons?
Replies:
As far as I know, gluons have a color charge, it is the combination
of a color ith an anticolor.
I have read in many places that due to SU(3) simmetry properties,
there are only 8 gluons, but I can't figure out wich one are them.
Using a simple combination, gluons could be redantiblue, red
antigreen, redantired, blueantired, blueantigreen, blueantiblue,
greenantiblue, greenantired and greenantigreen. (9 kinds of gluons)
Since three of them have a white color (redantired, blueantiblue
and greenantigreen) I can eliminate them, but then I only have 6
gluons.
Where does the number 8 come from?
To be truly white, the gluon must be redantired, greenantigreen, AND
blueantiblue. Based on the mathematics of wave function probability, the
white gluon is (redantired + blueantiblue + greenantigreen)/sqrt(3). The
square root of three is to keep things the correct size. There are tow wave
functions that are not actually white: (redantired 
greenantigreen)/sqrt(6) and (redantired + greenantigreen 
2*blueantiblue)/sqrt(6). These two gluons can interact without changing
the color of a quark, but they are not truly white. A white particle can
have no preference for red, green, or blue.
Kenneth Mellendorf
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Update: June 2012

